OK, whether she is asking to switch times to make way for "Uncle Fester" is neither here nor there. It's a matter of you two being co-operative with each other as long as the request is reasonable. You don't know why she's made the request anyway, you're supposing. Stop supposing and say yes or no based on your availability versus judging her need. You can date whoever you want and she can date whoever she wants. Let it go and concentrate on co-parenting and just co-parenting. That's enough to tackle with packing toxic emotion in there every time there's a request. That's my 2 cents anyway.